C is a multi-purpose programming language that Dennis Ritchie and Ken Thompson developed at Bell Labs in the early 1970s. It has become one of the most widely used programming languages ever designed and has inspired many subsequent languages, which employ similar control structures.
Ritchie and Thompson invented C to facilitate programming the UNIX operating system on the PDP-11 computer, which was much more powerful than their original PDP-7 machine. The original UNIX was written in assembly language, but to fully take advantage of the PDP-11’s capacity, they decided to developed a new code. Thompson tried FORTRAN, but quickly abandoned it in favor of a new language he called B (likely a shorthand for BCPL, an early programming language). But B ran into trouble when programming on the PDP-11, and its designers soon shifted toward a second iteration they called C.
In 1978, Ritchie and Brian Kernighan published The C Programming Language, popularly known as “K&R,” to define the informal specifications of this language. The American National Standards Institute (ANSI) would promulgate an official C standard in 1989.
Dennis Ritchie, "The Development of the C Language"